SACRAMENTO (AP) -- California officials are using a standard bidding process for their plan to speed construction of the state's $68 billion high-speed rail line, but there are still outstanding questions about the inspection process that the Legislature should investigate, lawmakers heard at a hearing on the plan.

The joint Senate hearing was billed as an opportunity to safeguard the public's interest as lawmakers evaluate whether the agency charged with building the nation's first bullet train has addressed a series of organizational problems, including whether it has sufficient staff and expertise to handle the project.

The independent Legislative Analyst's Office outlined questioned lawmakers "may wish to ask," including whether the California High-Speed Rail Authority will "retain the ability to independently inspect construction in the manner of its choosing."

The Associated Press reported last month that a union representing state engineers questioned whether the project would have sufficient independent inspection, since the firm being hired to design and build the first phase would hire the inspectors who test the work on it, which the union said could be a conflict of interest.

"There is no final quality program and no independent inspection process yet," policy analyst Brian Weatherford told lawmakers Tuesday. "... The extent to which there is a truly independent and direct inspection of the design builder's work is unclear."

Contractors submitted bids last month to design and build the first 30-mile stretch of track for the bullet train, a section that is expected to cost $1.8 billion. The first full segment of the system will run from Madera to Bakersfield, but the project eventually is supposed to link northern and southern California with trains traveling up to 220 mph.

The other outstanding questions include how the authority plans to assure the quality of construction materials, whether someone from the authority or project construction manager will be "present for each and every test and inspection conducted by the design-builder," and how it will evaluate potential conflicts of interest, the LAO said in its report to the Legislature.

Among the biggest concerns is how the state will fully fund the project. Lawmakers approved the first phase of the planned 800-mile line last summer, allowing the state to begin selling $2.6 billion in voter-approved bonds for construction of the first 130-mile stretch.

That approval also allowed the state to tap $3.2 billion from the federal government, but it's still not known where the rest of the money will come from. The state's business plan calls for some backing from private investors and for a private operator to run the system without a state subsidy.

Gov. Jerry Brown and most other Democratic lawmakers support the project, but it still faces intense criticism and a series of lawsuits.